Elastic-fluid turbine.



G. G. CURTIS. ELASTIG FLUID TURBINE.

APPLIUATIQN ULEB AUG. z. 1901. BBNEWED JULY 14. 1909. 985,982.

Patented Mar. 7.41911.

2 SHEETPBKBET l.

d'dir/1111i SEB Witnesses @h/f@ Att'ys.

muc

o. G. 0URTIVS.

` lBLASTIU FLUID TURBINE. Y

APPLICATION FILED AUG. 2, 1901. RENEWBD JULY 14, 19079.v

Patented Mar.7,1'911.

n smms-smm mmm Witnesses 'UNITED sTATEs PATENT OFFICE.

CHARLES G'. CUIRTIS, 0F NEW YORK, Y., ASSIGNOIL'BY MESNE ASSIGNMENTS, T0 GENERAL ELECTRIC COMPANY. A CORPORATION 0F NEW' YRK. Y

ELAsTIc-FLUID TIRBINE.

Specification of Letters Patent.

`Patented Mar. 7, 1911.

Application `filed August 2, 1901, Serial No. 70,615. yRenewed July f4, 1909. Serial No. 507,586.

To all 'whom 'it may concern:

Be it known that. I, CHARLES G. CURTIS, a citizenof the United States, residing .in the brough of Manhattan, city of New York, 5 State of New York, have invented a certain new and useful Improvement in' Elastic- Fluid Turbines, of which the following is a description.

The invention relates to elastic fiu'id tur- V10bin`es, operating on the principle of stage expansion, las described in my Patent No.`

566,969 dated September l, 1896. -t

The object of my invention to enable ,the expansion to be carried on in a considerable number of stages, and to enable'tbis to be done in anv apparatus which is as compact f andsimple as possible in construction. This I' accom lish by employing what I term interna ivstaging, methe rovision of means for producing and utilizing within a si le shell oneor'more stages of expansion in ad ition to that produced by the nozzle external to the shell, as distinguished from providing a separate shell for each stage of the expansion.

In carrying out my invention I may employ a jet nozzle, preferably of thel sectional character described in my application Serial No. 666,319 tiled January. 12, 1898, for producing the first stage offexpansion. This nozzle is applied to the head of the shell, and delivers the elastic fluid jet to' movable vanes within the shell,y which largely orl substantially abstract the velocity produced by the first stage of expansion. The steam jet, instead ofbeing discharged from the shell and delivered to a second nozzle external thereto and producing a. second vstage of .expansion which is .utilized in another shell, is delivered 'to a stage expansion device located .within the same shell. This device inclu es a stationary chamber Asupported from the shell in line with the movable vanesifrom which the steam jet is of expansion-,Ir he length of this chamber,

, lation to the turbine wheel, is great enough to cover all the movable vanes from which the section is secured to form-areceiving chamber or bowl adapted to deliver the fluid to discharged in the" iitilization of the first stageV steam is discharged. The chamber is en. `larged in its height, or radially with relation I the next element of the combination. This chamber I call an intermediate chamber. It receives and largely confines the steam delivered from the preceding stage, and delivers it in turn to the nozzle of the succeeding stage. The intermediate chamberis di- .vided by radial partitions into sections, so that portions of the steam jet' having different pressures 4may be kept separated and eiectively utilized in the subsequent passages of the apparatus. The intermediate chamber, from its enlarged center,A contracts lon curved lines' on its discharging side, where it is connected with the throats'of the sections of a second sectional nozzle, which delivers the steam jet to a second set of movable vaues.` The contracting side of the intermediate chamber, divided by its artition's into sections which correspond an register with the sections of the second sectional nozzle, forms a series ot bowls or enlarged portions anterior to the throats for the sections of the second nozzle, and hence -the discharging side of the Yintermediate chamber may be `regarded as a part of the nozzle into which it delivers the steam, because on this side 'of that chamber, the steam, as it flows toward the throats of the nozzle sections, has its pressure converted into velocity. The intermediate chamber may therefore be regarded as terminating, and the second nozzle as beginning, at the point ywhere the intermediate chamber begins to contract toward they throats of the nozzle sections.

The second nozzle is made sufficiently larger vice may be putwith-in the same shell. To

reduce the lossesdne to leakage, the clearances on the two sides of each internal stage expansion device are cut ott from the interior y of the shell and connected vtogether by a solid circular band connecting the wheelsy which support the adjacent movablevanes. This feature of internal staging .may be emplayed-to produce a stageexpansion turbine having all the stages of expansion' utilized in a single shell, or the turbine may have two or more shells in each of which the Yanes, means for delivering the elastic fluid to the first set ot vanes to produce a'zpart'ial conversion of the pressure of the elastic'` fluid into velocity, anda stage expansion device located `Wit-hin the same shell `between each set of vanes and the next, the said device' 4being so arranged as to receive theV elastic fluid from the preceding set-of vanes Without substantial velocity and deliver such elastic fluid into the succeeding set of vanes with a velocity produced by a further conversion of pressure into velocity.

(l. In an elastic tluid'turbine, the combination With a single shell, of an annular openino' therein containing two or more sets of ve ocity utilizing-venes, each set comprising two or more sets of movable vanes and onev or .more sets of intermediate stat1onary vanes, means for ldelivering the elastic fluid to the first set of vanes to producel a partial conversion of pressure of the elastic fluid into velocity, and a stage expansion device located Within the same shell between each set of vanes and the next, the said device being so arranged as to receive the elastic fluid from the preceding set of vanes Without substantial velocity, and deliver such elastic fluid to the succeeding set of vanes wtha velocity producedby al further conversion of pressure into velocit 5. An elastic lui turbine of the axial flow type, havin an annular opening and buckets exposed t erein, the said opening increasin in radial width to a point nearer to the inlet than to the outlet and then de` creasing in width to said outlet. 1

6. The combinat'on of an elastic Huid turbine of the axial flow type, having an annular opening provided with a contracted inlet and a contracted outlet, parallel buckets exv posed in said openings, each of said buckets being curved with the `apex of curvature nearer -to the inlet than to the outlet of the annular opening.

7. The combination of an elastic iiuid turbine of the axial flow type, having an annular opening provided with a contracted inlet and a contracted outlet, parallel buckets ex- Copies ot thisvpatent may be obtaimid for posed in said opening, each of said buckets having straight Walls connected by a curved portion, the apex of curvature being nearer' tracted outletg the inlet of sa'd; partition opening registerin Withthe outletof said wheel opening, bnc ets in saidzjawheel open'- ing and guide" blades in said partition open- With the apex of.. curvature nearer to the inlet than to theoutlet'of its o nings. 9, In an elastic tiuid tur ine, ,the combination with. a single inclosing shell, ofA

two or more velocity developingA and utilizing passages, each such passage being connected with the'succeeding one by an intermediate chamber having a larger cross-sec- `infg,each otrsaidguide blades being curved tional areathan such passage, substantially as described. i

10. In an elastic fluid turbine operating by stage expansion, the combination with a single shell and two sets of movable vanes therein,of a stage expansion device located between said sets of movable vanes and comprising an enlarged divided chamber receiving the elastic fluid discharged by one set of vanes, and a sectional nozzle connected with saidenlarged chamber on its discharg ing side andl directing the elastic fluid to the second set of vanes, substantially as set forth.

11. In an elastic fluid turbine operating by stage expansion, the combination with aV single shell and two Vsets of movable vanes therein, of a stage expansion device located within said shell between said sets of movable vanes, and a circular band or partition cutting oil' the clearances at. the opposite sides of the internal stage expansion device' f'rom the shell and connecting them together, substantially as set forth.

12. In combination with two bucketwheels of the axial flow type, a passage for working fluid interposed betweenv the said wheels having its cross-sectional area'gradually increasing, then gradually decreasing, and thengradually increasingin the direc tion of flow; the inlet extremity of said passage being equal in radial Width to the outlet of one wheel and the outlet extremity of said passage being equal in radial Width to the inlet of the other Wheel.-

13. The combination in an elastic fluid turbine of the axial flow type, of a wheel having an annular opening and buckets exposed therein, and a Wheel casing havlng a fixed partition parallel to the exhaust side of the said Wheel, provided with an annular opening having a contracted inlet and.a contracted outlet and guid lblades 1n said partition opening, the inlet of said partition opening registering with the outlet of said ve 'cents each, by addressing the commissioner of Patents, Washington, Il. C. 

